Chlamydia psittaci infections in Chinese poultry: a literature review

Chlamydia (C.) psittaci, formerly known as Chlamydophila psittaci infections cause important economical losses to the poultry industry and are a danger to public health. The economic and zoonotic impact of C. psittaci infections in the Western poultry industry is well documented. Less is known on its occurrence in Asia. In the following review we address C. psittaci infections in Chinese poultry in view of China supplying 40.8% of global egg production and 14.2, 69.3 and 91.1% of global chicken, duck and goose meat, respectively. The current paper compiles English and Chinese scientific literature on C. psittaci infections in Chinese poultry. The paper is focusing on seroprevalence, culture, direct antigen detection, molecular characterisation, observed symptoms, Chinese traditional medicine and psittacosis case reports. A review on the epidemiology of chlamydiosis in Chinese poultry clearly illustrates the widespread presence of virulent C. psittaci strains in chickens, ducks and geese across China. In Western countries, C. psittaci infections in poultry are principally treated with antibiotics. In China, however, herbal medicine is often used in conjunction with antibiotic treatment or as prophylaxis. The applied production and marketing systems facilitate zoonotic transfer. Chinese occupationally acquired psittacosis cases include reports on infections contracted from ducks, pigeons, chickens and peacocks.